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I have heard a lot about polygonal rifled barrels and, lots of controversy regarding is it better or is it not better. I would like to know what the general memberships thoughts are regarding this and, what are the advantages and or disadvantages.
 

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it seals gasses better (more velocity) and fwiw, it's easier to clean (no ridges between land and grooves where carbon gets stuck) supposedly more accurate too, but unless you are a bench shooter, it's not going to matter.
 

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Only other caveat I can think of is that lead bullets are a no no in polygon barrels. Glock pistols for instance

But it's doubtful any of you are going to load those for your battle rifle. If i ever need to do that my Mauser 98 in 7.62 NATO will get the lead projectiles
 

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Only other caveat I can think of is that lead bullets are a no no in polygon barrels. Glock pistols for instance
Maybe one day this urban myth will be put to rest. Lots of reloaders shoot tons of lead bullets in their polygonal barrels... Glocks, HKs, etc. BTW, brand doesn't matter; a polygonal bore is a polygonal bore is a polygonal bore...

Yes, you have to pay attention to ensure you have no excessive lead build-up. This is easily controlled by a knowledgable reloader and simply dealt with if it DOES occur... just run a brush through the bore a few times every 150 rounds or so. I have shot many thousands of cast lead bullets through a variety of HKs and two Glock 19s, with absolutely zero ill effects.

As to accuracy, dunno. All my HKs are phenomenally accurate (when I do my part), but I'm not so sure if that is due to HK's increased quality control/precision manufacturing more than the polygonally rifled bore. One real tell-tale is that you rarely see a drag mark on a fired case out of an HK. This means that the piece is timed properly and the barrel isn't unlocking prematurely. Happiness through better manufacturing... :)

One other, not-so-well-known characteristic of polygonal bores is that they make forensically identifying bullets shot out of one rather difficult. It can be done if all the planets line up, but not often. Some manufacturers actually offer a special, unique process (for an extra fee, of course) that solves this issue. That said... don't make the mistake of thinking you can smoke someone with your Glock and you're home free. There are other ways of determing what was shot out of which gun... :wink:

.
 

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I have put over ten thousand rounds of lead cast bullets through 3 USP pistols with no problems. However my new 9mm compact leads to much so I am trying copper plated bullets at .08 cents apiece to see how they work.
 

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why would lead be a problem in a poly barrel? if anything I would think there would be less lead build up as the edges of rifling isn't cutting into the lead and taking on deposits.
 

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The only difference from a rifled(lands and grooves) barrel is that the polygonal is easier to clean and does not leave marks on the bullet after it passes through it. Anything about it being more/less accurate is totally dependent on the individual. You do get higher velocities due to the better seal around the bullet, but not so much that it would be noticeable to the average shooter. To answer the original question, i personally don't have a preference of one over the other. Having shot and owned both kinds i have to say that this would be one of the last things i ever consider when shooting/owning a weapon. To be honest though, mentioning that my USP has a polygonal barrel is one of the ways i like to one-up my non-HK-owning buddies.
 

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Things I've heard:

1) Polygonal bores are more accurate
My thought: Well, there sure are a lot of accurate land and groove bores out there.

2) Polygonal bores last longer.
My thought: I think it has more to do with the quality of the barrel than the bore type. In Todd Green's endurance tests, just like the HK's the M&P didn't lose any accuracy after 63,000 rounds.

If HK switched to a conventional land and groove, I couldn't care. I think the fact their bores can fire through a squib and still make accuracy standard is due to their quality of materiel/manufacturing/QC rather than the bore type. Same with accuracy/longevity in normal use.
 

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Everyone says that poly barrels are easier to clean, but my Glock and usp barrels are a bitch to clean compared to other guns I've had. I don't know why. Same ammo, cleaners, and techniques. And the poly barrels being more accurate I feel to be a selling point, not actual fact. Military arms channel on YouTube benches his mr556 against an Olympic arms m4 and has marginal at best results in accuracy, ymmv. But like others have said, if hk barrels can handle squibs being shot out of them, they can do whatever they want with their barrels.
 

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Maybe one day this urban myth will be put to rest. Lots of reloaders shoot tons of lead bullets in their polygonal barrels... Glocks, HKs, etc. BTW, brand doesn't matter; a polygonal bore is a polygonal bore is a polygonal bore...

Yes, you have to pay attention to ensure you have no excessive lead build-up. This is easily controlled by a knowledgable reloader and simply dealt with if it DOES occur... just run a brush through the bore a few times every 150 rounds or so. I have shot many thousands of cast lead bullets through a variety of HKs and two Glock 19s, with absolutely zero ill effects.

As to accuracy, dunno. All my HKs are phenomenally accurate (when I do my part), but I'm not so sure if that is due to HK's increased quality control/precision manufacturing more than the polygonally rifled bore. One real tell-tale is that you rarely see a drag mark on a fired case out of an HK. This means that the piece is timed properly and the barrel isn't unlocking prematurely. Happiness through better manufacturing... :)

One other, not-so-well-known characteristic of polygonal bores is that they make forensically identifying bullets shot out of one rather difficult. It can be done if all the planets line up, but not often. Some manufacturers actually offer a special, unique process (for an extra fee, of course) that solves this issue. That said... don't make the mistake of thinking you can smoke someone with your Glock and you're home free. There are other ways of determing what was shot out of which gun... :wink:

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OK you are just wrong. Glock specifically renigs on their warranty beacuse of this issue and it makes sense since you cannot easily determine how much lead you have built up in a polygonal barrel! You use it at risk of your life/health and voiding the warranty..
 

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why would lead be a problem in a poly barrel? if anything I would think there would be less lead build up as the edges of rifling isn't cutting into the lead and taking on deposits.
Because you cannot easily see how much you have built up (and how much must be removed) as you can in a rifled barrel. Likely some people are one shooting trip from a kaboom. The manufacturers have warned you, now it's your choice
 

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Because you cannot easily see how much you have built up (and how much must be removed) as you can in a rifled barrel. Likely some people are one shooting trip from a kaboom. The manufacturers have warned you, now it's your choice
I see... I would clean my barrel with good lead remover after everytime I shot lead... odd
 

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I have yet to see a test with equipment to measure the velocity difference between a rifled bore & polygonal barrel (with chambers, lengths & standards all the same) done so I can see the actual results. If someone has a chronograph, several weapons with these characteristics, ammunition and lots of time, please post the results for us to see. Comparing one gun to another just won't do. I would like to see a selection of ammunition, types of weapons from pistols to long guns and the numbers.

Until I do, I'm pleased with my guns shooting better than I do, and on a regular basis. Quality of manufacture, engineering, metallurgy and design still count for something to me.
 

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I have yet to see a test with equipment to measure the velocity difference between a rifled bore & polygonal barrel (with chambers, lengths & standards all the same) done so I can see the actual results. If someone has a chronograph, several weapons with these characteristics, ammunition and lots of time, please post the results for us to see. Comparing one gun to another just won't do. I would like to see a selection of ammunition, types of weapons from pistols to long guns and the numbers.

Until I do, I'm pleased with my guns shooting better than I do, and on a regular basis. Quality of manufacture, engineering, metallurgy and design still count for something to me.
The USP started life with conventional barrel, for I think the first two years of production. So just find a very early USP, buy a new barrel from HKParts and use it in the same gun to run some chrono tests.

-Sean


Typoed on my iPhone.
 

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Because you cannot easily see how much you have built up (and how much must be removed) as you can in a rifled barrel. Likely some people are one shooting trip from a kaboom. The manufacturers have warned you, now it's your choice
Manufacturers also caution that reloads will void a warranty too...yet many of us shoot our own reloads. I shoot nothing but lead in my pistols up to and including 357Sig with little to no leading in any of my barrels...that includes polygonal barrels in my H&K P30 and P2000, a G19, and a Kahr K40. My experience is that polygonal barrels exhibit leading much less than conventional rifling and are much easier to clean. I recently shot 850 rounds of 357Sig lead reloads through my P2000 (mt EDC) at an average velocity of 1325 fps without so much as running a boresnake through it (which I generally do every 200 rounds or so)...One shot of HOS and a couple swipes with a boresnake and the bore was a good as new. I also don't understand why you say you can't tell how much lead buildup there is in a polygonal barrel. If it shines like a mirror when I look at it and I can see the corners of the grooves, it's clean. If I can't, it's dirty and/or leaded.
 

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OK you are just wrong. ..
LOL. No, YOU are. As noted above, all manufacturers warn against reloads to cover themselves from being sued by idiots who can afford a reloading press.

But that's okay. Bask in your smug self-assurance... in the meantime, many of us will shoot a lot more than we could otherwise afford to... healthily and safely.:wink:

.
 

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There are too many people who do not have any experience or know much if anything at about loading lead cast bullets trying to give advice or warning us about or impending death from lead build up in barrels. They simply are regurgitating some misinformation they have read from some else on a forum who is just as ignorant about it as they are. If you shoot lead bullets at a lower velocity or use a quality bullet lube you will not get any lead in your barrel. I have nearly a 55 gallon drum worth of lead through my USPs to back that up and if someone says you can’t see lead in a barrel then they obviously completely ignorant about shooting lead bullets.
 

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I cast my own and have reloaded them since 1985 but i won't shoot lead in a polygonal bore.. there are very nice aftermarket standard rifled barrels and that is the way I go
 

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LOL. No, YOU are. As noted above, all manufacturers warn against reloads to cover themselves from being sued by idiots who can afford a reloading press.

But that's okay. Bask in your smug self-assurance... in the meantime, many of us will shoot a lot more than we could otherwise afford to... healthily and safely.:wink:

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The warning is specifically about lead in polygonal bores.. I shoot my own reloads but not lead in a poly barrel..do what you like
 

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I have yet to see a test with equipment to measure the velocity difference between a rifled bore & polygonal barrel (with chambers, lengths & standards all the same) done so I can see the actual results. If someone has a chronograph, several weapons with these characteristics, ammunition and lots of time, please post the results for us to see. Comparing one gun to another just won't do. I would like to see a selection of ammunition, types of weapons from pistols to long guns and the numbers.

Until I do, I'm pleased with my guns shooting better than I do, and on a regular basis. Quality of manufacture, engineering, metallurgy and design still count for something to me.

OK, I don't have any printed material to show you because we didn't write it down. All we had were the chronograph paper with the velocities on it.

I work for a custom rifle maker in Phoenix. We took a 24" barreled 308 with a Gary Schneider P5 rifled polygonal barrel and another gun with a Gary Schneider 24" land & grooved barrel to the range. We took several boxes of 168gr Black Hills Match ammo with us. We also took one of our 308, 20" poly barreled TAC guns with us.

We found that the polygonal rifled was 250 fps faster than the land & grooved gun. We also found that the 20" gun was only 50 fps slower than the 24" P5 gun.

Which stays cleaner? The P5 rifled gun by FAR. Our general manager shoots match. He has done a 450 round match with NEVER putting a patch thru the barrel!!He did win his match, setting a new record along the way. He prefers to have a smoke instead of cleaning between legs!

We actually have a line of guns using the poly rifles as their main selling feature! We are able to go to a 26" barrel from a 28" just because we use the P5 barrels in 338 Lapua!

You have any questions, PM me.
 
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